1. Field of the Invention
The present invention relates to a hydraulic pumping cylinder, and, more particularly, to a low-load rapid fluid movement pumping cylinder.
2. Description of the Related Art
Hydraulic cylinders are common devices used in industry and for the jacking of loads using a jacking mechanism having a input cylinder and an output cylinder. The output cylinder is used to lift the load to a predetermined height with a considerably small force utilized on the mechanical portion that moves the input cylinder. The working principal of the hydraulic jack system provides for an applied small force that moves the input piston of a small cross-sectional area and pushes the hydraulic fluid or oil into an output cylinder, which then forces an output piston of large cross-sectional area to jack up a load.
The path of the input piston is often far longer than that of the output piston. The input piston must be repeatedly pumped to jack a load to a predetermined position. During the jacking process, each stroke of the input piston moves the output piston based upon the fluid transfer from the input cylinder to the output cylinder. Typically the same number of pumping strokes is needed to move the jack to a predetermined height regardless of whether there is a load on the output cylinder or not. Under the no-load condition the rate at which the ram of the output cylinder extends, directly or by way of a lifting arm, is not noticeably changed from the rate at which it travels under a loaded condition.
A disadvantage of the systems presently in use is that time and energy are wasted in moving the output piston/ram to the desired location or to encounter a load which is to be moved and/or lifted. Solutions utilized prior to the present invention typically utilize many hydraulic components, which are complex and expensive to manufacture, and due to the additional number of parts are often unreliable.
What is needed in the art is an easy to operate and inexpensive to manufacture pumping cylinder system that moves a large quantity of hydraulic fluid under low pressure yet delivering high pressure when a load is encountered.